Industrial engineering calculator
Calculate how many operators a line needs to meet a daily target from garment SMV, working hours, planned efficiency and an absenteeism buffer.
Operators to plan
41persons
Operators = target × SMV / (working minutes × efficiency) / (1 - absenteeism)
| Symbol | Meaning | Unit |
|---|---|---|
| Q | Daily target | pcs |
| T | Working minutes per day | min |
| η | Planned efficiency | - |
| a | Absenteeism as a fraction | - |
Work content = daily target × SMV. Minutes per operator = working minutes × efficiency. Operators present needed = work content / minutes per operator. With an absenteeism buffer, the planned number = present needed / (1 - absenteeism), rounded up.
Defaults: target 1,000 per day, SMV 12.0, 8 hours, 65% efficiency, 5% absenteeism.
Use the result to size a line for a new order, then check the machine mix with the machine requirement calculator. If you cannot staff the line, calculate the achievable target with the production target calculator.
If a line is staffed for exactly the people needed, every absence reduces output. The buffer plans extra people so the expected number present meets the requirement.
It includes everyone who carries a share of the garment SMV. If your SMV excludes helper work, plan helpers separately.
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